Coordinated MultiPoint (COMP) transmission/reception is an advanced technology for cellular communication networks to improve coverage, support high data rates, improve cell-edge throughput and/or to increase system throughput.
Uplink COMP generally implies coordination among multiple geographically separated reception points, and downlink COMP generally implies dynamic coordination among multiple geographically separated transmission points. In general, the basic idea is to perform joint detection in the uplink by jointly processing radio signals received at multiple points, and likewise to perform joint transmission in the downlink by coordinating transmission from multiple points to one or more user terminals.
As an intermediate step towards general COMP operation, so-called intra-site cooperation has been proposed, where different sectors of the same radio base station are coordinated.
It is also possible to coordinate different sectors belonging to different sites, so-called inter-site cooperation, where the data has to be exchanged between the involved radio base stations, or more generally access points, via the so-called backhaul network.
For the uplink, the entity responsible for decoding, typically one of the access points such as a serving radio base station, may thus collect samples from other access points via the backhaul network, and include them in the decoding of the user.
However, it still remains to decide if it is really beneficial to use more than one access point in the uplink and if so which access points to use for COMP uplink reception.